Means for maintaining pressure on liquid for use in vehicle braking



Dec. 11, 1928.

J. S. REYNOLDS MEANS FOR MAINTAINING PRESSURE ON LIQUID FOR USE INVEHICLE BRAKING.

Filed Feb. 16. 1926 i mi,

INVENTOR Joy /fwyows ATTORN EY Patented Dec. 11, 1928.

UNITED STATES PATENT OFFICE.

JOY s. REYNOLDS, or DETROIT, MICHIGAN;

MEANS FOB MAINTAINING- PRESSURE ON LIQUID FOR USE IN VEHICLE BRAKING.

Application filed February The .resent invention is an automatic meanstor maintaining pressure on llquid i'or use in vehicle brakmg.

The principal object. of my invention isautomatic cut-out-mechanism. Inhydraulic brake systems it is customary to create a pressure 1n astorage tank by pumplng liquidinto a closed container and therebycompressing air', or other expansive medium, to react in the subsequentdischarge of said liquid to the work to be done. This inventioncontemplates the use ofthe weight of the'body of a vehicle which isdirectly ap- .plied on a relatively small quantity of liquid to createthe required pressure.

It results from this method that. in case of repeated operations, thelast operation willbe accomplished with exactly the same workingpressure as the first. This is not the case' where' expansive mediumsare emy ployed".

One distinct advantage of my invention is that t-he degree of pressureavailable to apply brakes to a vehicle will always be in exactproportional relation to the load carried bythe vehicle and willautomatically' fluctuate therewith.

In this specification and the annexed drawings, the invention isillustrated in the form considered to be the best, but it is not limitedto such form because it may be embodied in other forms, and it is alsoto be understood that in and by the claims following the description itis desired to cover the invention in whatever for'm it may be embodied.

In the accompanying drawings Figure 1 is afragmentary view of a chassisof an automobile showing an engine and :i rear wheel brake element.

Figure 2 is a diagrammatic view partly in section, of a detail andshowing its relation to the brake mechanism.

Referring to the drawings the numeral 1 frame 6. I choose to interposeat one end between spring 4 and frame 6. a Vcylinder 7 pivotallyconnected at 8 to the trame 6. Re-

16. 1926. Serial No. 88,514.

ciprocable in cylinder 7 is a piston 9, the outer .end of which .isslotted to admit the eye ot the major leaf of spring 4 which ispivotally engaged with piston 911V a Pin 11- 60 At 12 I show a quantityof liquid in cylinder 7 At 13 I show a packing nut for holding the usualpacking andfor guiding the outer end of piston 9. In Figure 1, at 16, Ishow an automobile engine. ing part thereof, or from a suitable powertakeoff, I derive power to operate a pump shown in Fig. 2, at 17.

The arrangement is such that the pump is driven continuously when theengine runs.

Said pumpV is provided with an intake 1S governed by a check valve 19,and with a discharge 21 governed by a discharge check 22. Intake 18 isat the bottom of a liquid container 23. The discharge end 21 of the 75pump is connected to one end of -pipe 24, t-he opposite end of which isconnected `to a T 26. To one leg of T 26 I connect one end ot a pipe`27, the opposite end of which is connected to cylinder 7, near the topthere- 8o of. To the remaining leg of T 26 I connect one end of a pipe28, the opposite end of which is connected-tothe intake orilice 31 oil acontrol vvalve 32. To an outlet oriice 33 ofcontrol valve,32 I connect-one end of 85 a pipe 34, .the opposite end of which is connected to acylinder 36 containing )iston means for expanding a brake drum 3 in awell known manner.

At 38 I show a discharge port adaptedhuu when the control valve isoperated to release brakes to spill into the reservoir 23.

The control valve 32 is described and claimed in United States Patent1,474,164

,issued to me on November 13, 1923. Assumthe vehicle frame and its load)through pipes 27 and 28, through said control valve 32 and through pipe34 to the expanding mechanism of brake band 37. This completes the brakeapplication.

To release the brake the stem of control valve 32 is released, at whichtime the urge of springs 39, contracts brake band 37, forcing liquidback through pipe 34 to the control valve 32. The position of the valveis such that liquid from pipe 34 is discharged no through the dischargeorifice 380i said valve to the bottom of the reservoir 23. As soon Fromany mov- 65- as liquid ravitates in reservoir 23 the pum 17 (runningcontinuously) picks it up an forces it through pipes 24 and 27 to thecylinder 7 thus replenishing the system for repeated operation. Thecylinder 7 is so proportioned that several brake applicationsmay be madein rapid succession without said cyl-.

inder being depleted faster than the pump can replace liquid therein.

The capacity of reservoir 23 is sucient to receive all the liquid in thesystem in case several brake applications were made while the engine wasnot running. As soon as the engine is started again the hydraulic brake`system will be immediately and automatically restored to operation.

It 1s understood that in the arrangement shown the pump does not ceaseoperation ,l during operation `of the engine but operates continuouslyand the cylinder-7 is to be understood as of a capacity to contain thebetween the frame o said` vehicle and reliquid of the receptacle andthus if the liquid in the receptacle1 is depleted to below the inlet 18liquid ceases to be discharged tothe cylinders but is returned to thereceptacle upon application of the brake.

I claim: y 1. A means for maintaining pressure on liquid for use invehicle braking comprising' means interposed between the body of saidvehicle and its spring suspension-for creating pressure on a quantity ofliquid, means for releasing said liquid under pressure to effect a brakeapplication, and means for restoring said liquid to its source upon thelrelease ofrsaid brake application.

2. An automatic means for vmaintainingsaid cylinder silient supporttherefor, a vpiston reciprocable in said cy inder and secured to one ofsaid members, a pipe connecting said cylinder with a brake operatingmechanism, a reservoir interposed in said ipe line, control valve meansassociated with said pipe line for, selectively, applying said brakemechanism hydraulical y from said cylinder for discharging li uid'tosaid reservoir to release said brake mec anism, and means' for returningli uid from said reservoir. to said cylinder or repeated operation. l

4. An' automatic means for maintainin pressure on liquid operated brakesystems for vehicles comprisin a cylinder interposed between the frame osaid vehicle and resilient support therefor, a piston reciprocable insai cylinder and secured to one of said members, a pipe connecting saidcylinder with a brakeoperating mechanism, a reservoir interposed in saidVpipe line, control valve means associated with said pi e line for, se'-lectively, applying said brake mechanism hydraulically from saidcylinder for dischargin liquid to said reservoir to release said bra emechanism and means for returningliquid from said reservoir to saidcylinder for repeated operation, said means deriving its power from thepropelling mechanism of sa1d vehicle.

5. That method of vehicle braking which consists iny interposing aliquid container between the body of a vehicle and its sup- .i

-port to create ressure on said liquid, applying brakes hy raulically bythe use of said liquid under pressure, and returning said liquid-to its'source to make the system automatically regenerative. l

6. In Acombination `with an automobile frame provided with a springsuspension and with hydraulically operated brakes, a liquidA containerinterposed between vsaid frame and said spring suspension, piston meansin said cylinder for causing the weight of said body to create pressureon liquid in said container, a pi e circuit including saidcylmder andsaid rake .mechanism and means interposed in said circuit for divertingliquid under pressure from said container to ap ly said brakes and meansinterposed in sald) circuit for returning liquid used in application ofsaid brake to said container.

In 'testimony whereof I ailx my signature.

' JOY S. REYNOLDS.

